#  字典的增删改查练习

zd = {}
zd[1] = 'zc'
zd[2] = 'mz'
print(zd)
zd[2] = 'cz'
print(zd)
zd.pop(1)
zd[1] = 'cz'
print(zd)
for k, v in zd.items():
    print(k, v)
